GB779197A - Improvements in apparatus for processing a textile sliver or other continuous body of textile material - Google Patents

Abstract

779,197. Electric control systems. T.M.M. (RESEARCH), Ltd. May 25, 1955 [May 26, 1954], No. 15564/54. Class 40 (1). [Also in Groups IX and XXXVI] Apparatus processing a textile sliver or other continuous run of textile material comprises a device deriving mechanical or electrical signals due to measured variations of a physical characteristic thereof which operates means generating electric signals proportional in amplitude to the instantaneous values of the characteristic, which are then converted into a train of electric pulses of widths proportional to such instantaneous values, which are stored in a continuous record and after a predetermined time delay are reproduced as further signals actuating mechanism whereby the textile material is treated for the removal or reduction of the variable characteristic. A textile sliver 11 (Fig. 1) passes to drafting rollers A, B through transducer 10, which generates a signal of amplitude varying proportionally to the instantaneous thickness for conversion by device 12 to a pulse train of frequency inversely proportional to the instantaneous signal amplitude, which is shaped by device 13 to a train of square pulses of widths instantaneously proportional to the thickness, which are magnetically recorded by head 14 on a tape 15 driven at constant speed by the back pair A of the drafting rollers. A magnetic pickup 16, movable with regard to the recording head 14 to control the insertion of a time delay, reproduces the pulse train recorded as an electrical signal, which after amplification and squaring by device 17 is differentiated to trigger a sawtooth generator 18, whose output is proportional in amplitude to the input pulse width and is smoothed at unit 19 to a control signal for the variable speed driving mechanism 20 of the front pair B of the drafting rollers, whereby the draft speed is controlled, after a time delay by the occurrence of a thickness variation, in such a sense as to reduce such variation. The recording head may have the form of a roller (Fig. 2, not shown) against which the tape is pressed by a spring arm, and after reproduction the recording is erased by a permanent magnet. The signals may alternatively be recorded magnetically on a disc rotating in synchronism with the draft rollers.